Method of cleaning and stimulating a water well

ABSTRACT

Provision is made for recycling well fluid by extending a recycle line from the pump discharge to the well casing below the pump apparatus without interfering with or requiring a modification or removal of the apparatus. The recycling line includes means for the regulated introduction of cleaning solutions. The recycled fluid and solutions fall freely down the well casing and clean the interior of the casing and the exterior of the well column, along with the interior of the well column upon a repumping of the fluid. The fluid falling downwardly within the casing exteriorly of the well column impacts with the water standing in the lower portion of the casing and generates substantial energy waves which are transferred to the aquifer which in turn stimulates and benefits the well.

United States Patent Jenkins 1 1 Aug. 12, 1975 [54] METHOD OF CLEANING AND 3,122,503 2/1964 Katzer 166/312 x STIMULATNG A WATER WELL 3.547,l94 12/1970 Morine 166/312 X [76] Inventor: Jerold D. Jenkins, 404 Mills,

Dumas, Tex. 79029 [22] Filed: Apr. 19, 1974 211 App]. No.2 463,044

Related US. Application Data [63] Continuation of Ser. No. 47,832, June 19, 1970,

abandoned,

[52] US. Cl. 166/302; 166/249; 166/68.5; 166/312 [51] Int. Cl E211) 43/00; E21b 43/27 [58} Field of Search 166/312, 249, 311, 314,

[56] References Cited UNITED STATES PATENTS 1,599,744 9/1926 Chapman 166 56 1,693,405 11/1928 Sanford. Jr. 166/56 2,161,085 6/1939 Phalen 166/300 2,309,697 2/1943 Gunderson.. 166/62 X 2.322.484 6/1943 Stuart 166/312 X 2,386,605 10/1945 Harton, Jr. et a1. 166/312 X 2,773,551 12/1956 Warden et a1. 166/67 X 2,802,537 8/1957 Goldinger 1 166/312 3,073,390 l/l963 Beckett 166/312 X OTHER PUBLICATIONS Babbitt, Harold E. et 211., Water Supply Engineering, N.Y., McGrawl-lill, 6th Ed., 1962, pp. 75-77.

Primary ExaminerStephen J. Novosad Attorney, Agent, or Firm-Clarence A. OBrien; Harvey B. Jacobson [57] ABSTRACT Provision is made for recycling well fluid by extending a recycle line from the pump discharge to the well casing below the pump apparatus without interfering with or requiring a modification or removal of the apparatus. The recycling line includes means for the regulated introduction of cleaning solutions. The recycled fluid and solutions fall freely down the well casing and clean the interior of the casing and the exterior of the well column, along with the interior of the well column upon a repumping of the fluid. The fluid falling downwardly within the casing exteriorly of the well column impacts with the water standing in the lower portion of the casing and generates substantial energy waves which are transferred to the aquifer which in turn stimulates and benefits the well.

6 Claims, 1 Drawing Figure upar EIanmd Com :Sralie Wafer Laval Draw Down Cbne umping Wa ter Laval METHOD OF CLEANING AND STIMULATING A WATER WELL This is a continuation of Ser. No. 47,832, filed June 19, 1970 now abandoned.

The instant invention is generally concerned with the cleaning and benefitting of wells, and more particularly relates to a unique system which relies on a recycling of the fluid from the well pump whereby the entire discharge from the pump is recycled through the well and surrounding aquifer along with selectively introduced cleaning solutions.

There are of course many ways of benefitting or stimulating wells, most utilizing expensive and complicated equipment requiring a removal of the pump apparatus and a forcing of appropriate solutions under pressure down the well column. It is a primary object of the instant invention to provide a unique means for cleaning a well which eliminates the expensive equipment and procedures associated with more conventional methods and relies basically on a simple although highly unique system whereby the pumped fluid from the well itself is recirculated along with selectively introduced cleaning chemicals.

Another significant object of the instant invention resides in the provision of means whereby precise amounts of chemical additives can be introduced, with the concentrations being cycled through the well accurately controlled.

Another important object of the instant invention resides in the provision of an apparatus which can be mounted on a well without removing or in any way interfering with the pump apparatus or related equipment.

Further, an important object of the instant invention resides in the provision of a cleaning system wherein the entire inner surface of the casing, as well as the inner and outer surfaces ofthe well column and the surrounding aquifer, are subjected to the cleaning action.

The system herein is also so devised as to, through a free falling of the pump fluid back down the well casing to impact with the water standing in the lower portion of the casing, generate substantial shock wave energy which is transmitted to the surrounding aquifer, producing a cleaning action therein so as to stimulate the well and improve the yield therefrom.

Basically, the objects of the invention are achieved through providing fluid recycling piping from the pump discharge to the well casing below and in spaced relation from the pumping apparatus so as to not interfere therewith. This recycling piping has appropriate means communicated therewith for the selective introduction of cleaning chemicals with such chemicals being introduced into the recycled fluid for a movement therewith down the well casing, out into the surrounding aquifer and subsequently back up through the well column. Appropriate control valves are provided for a selective purging of the well.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully. hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.

The FIGURE illustrates a well with the well treating system of the instant invention incorporated thereon.

Referring now more specifically to the drawings, reference numeral 10 is used to generally designate a well having the system of the present invention incorporated therein. The well itself is of conventional construction, incorporating a well casing 12, perforated at the lower portion thereof engaged with the aquifer 14, a central well column 16 and superimposed pump apparatus or equipment 18.

The apparatus associated with the treatingsystem is generally designated by reference numeral 20 and includes a recycling line or piping extending from the pump discharge, generally indicated by reference numeral 22, to the well casing 12. The engagement with the well casing 12 is made below the support pad 24 for Y the pumping apparatus and is effected by first digging a pity 26 outward of the pump assembly and subsethe pad 24, a hole is cut in the casing and'a pipe nipple 30 welded thereto so as to project generally laterally therefrom.

The recycling line or piping includes flexible rubber or plastic sections 32 and a central PVC section 34 with the flexible sections enabling an adjustment of the line to such variations as. may occur in different installations. It will thus be appreciated that the recycling line is installed without disturbing the pump apparatus.

A discharge line 36 branches off the recycling line. An enlarged manually controlled off-on valve 38 is located in the recycling line, and a similar valve 40 is located in the discharge line whereby a selective discharge or recycling of the pumped flow from the well can be effected as required or desired. A chemical tank 2 or supply-42 is located outward of the recycling line and communicated with the recycling line, below the valve 38, by means of a-hose or line 44 incorporating a pair of valves 46 at the opposite ends thereof. Through a selective manipulation of the valves 46 regulated amounts of solution can be introduced into the recycling fluid to achieve the desired cleaning action. While not limited thereto, the system of the instant invention can be utilized in effecting a three-phase cleaning operation. The primary object of the first phase is to clean up the well and eliminate fungus and other living matter from the well. This is effected by recycling the well fluid and introducing HTH, a product of Olin Mathieson Chemical Corp., consisting of concentrated potassium hypochlorite as a dry free-flowing powder containing '70 percent available chlorine. A concentration of from 500 to l000 parts per million is achieved, after which this solution is recycled from 2 to 4 hours. The well is then purged. A sampling of the solution can be effected through the discharge line 36 by an opening of the valve 40. By the same token, a purging of the well is effected by an opening of the valve 40 and a closing of the valve 38. The second phase has for its object to'place into solution as much clay as possible and at the same time condition the iron oxides, rust and incrustations, etc., for easy removal. This is accomplishedby recycling a solution of sodium hexametaphosphate of between to 500 parts per million. This is recycled from l5 to 24 hours, after which the well is again purged.

The third phase involves a cleaning of the perforations which is accomplished by injecting hydrochloric acid, inhibited at such a concentration as to protect all base metals. .Good resultscan be obtained by using a percentsolution for a period of 4 hours.

It should be'ap preciated that the concentrations and time can vary over a relatively wide range depending upon the particular circumstances involved.

It has also been found that the cleaning action can be enhanced by a selective repeated raising and lowering of the temperature of the well casing by the addition of an appropriate basic solution in such quantities as to produce an exothermic reaction. The heat generated tends to expand the casing, thereby aiding the chemicals in the removal of'incrustations and the like. By the same token, the expansion and subsequent contraction of the casing produces a rubbing action between the casing and the surrounding gravel pack. This action produces a better cleaning of the casing and a readjustment of the gravel pack so as to clean the area and produce a better filtering media.

As will be appreciated, a substantial amount of energy is produced by dropping the water from ground level to the staticwater level. Assuming a distance from the surface to the static water level of 200 feet, and a pumping of 600 gallons per minute, approximately one million pounds of energy per minute would be developed at the pointof impact at the static water level. This energy, coupledwith the downward movement of the solution, tends to create energy waves that will travel through the casing and'aquifer and greatly enhance tlie'clean'ing action. I

lnmore conventional systems, the treatment is usually effectedonly from the static level of the water downward'within the well casing. However, in the instant system, the concentrated solutions are recycled in such a manner as to completely cover the well along its entire length, covering all exposed areas of the casing and column, thereby eliminating the possibility of future contamination by organisms dropping therefrom into the water from above the static level.

During the normal operation of the pump, the water isdrawn down from the static water level into a cone of depression or a drawn down cone, generally-suggested in the drawing. However, during the recycling operation, it is theorized that the reintroduced water and the energy developed thereby will produce a superelevated cone-of some magnitude, this in turn developing addition pressures outward into the aquifer, along with an increased intensity in the cleaning action of the chemicals within the aquifer. In this manner, a further significant advantage is achieved through a utilization of the system of the instant invention.

Other advantages arrived atthrough the system herein described is the ability to add accurate and precise amounts of additives so as to achieve specifically desired concentrations, the solutions or additives being introduced through the recycling line. By the same token appropriate samples can be taken from the discharge line so as to determine the concentration. Should a decrease in the concentration be necessary, a simple purging of aportion of the flow can be effected. In addition, the recycling system of the instant inventioneliminates the necessity of removing the gear head, column and/or any additionalpump assembly apparatus. Further, the entire inside of the casing, as well as the inside and outside of the column is subject to treatment, thereby providing a better and long lasting effect particularly when treating algae and other types of growth, providing in effect'asterilized condition. Reliance on exothermic reactions also facilitates a sloughing off of incrustations and the like from the casing with the surging action of the reintroduced falling liquid increasing the chemical action and assisting in producing a highly effective cleaning action throughout the entire well system. As an examle, one manner of effecting a temperature control, above and beyond the temperature increase which can normally be expected from the.

principles of the invention. Further, since numerous modifications and'changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications-and equivalents may be resorted to, falling within the scope of the invention as claimed. i

What is claimed as new is as follows:.

l. The method of cleaning and stimulating a water well of the type including an outer casing extending downwardly into an aquifer and perforated at thelevel of the aquifer and with the well casing being closed at its upper end by a support pad and having a central discharge tubing extending downwardly through the pad and the casing to at least the perforated area of the casing with the outer surface of the tubing spaced from the inner surfaces of the casing, said method including the steps of digging a pit downwardly alongside the pad to a level therebelow and tunneling inwardly to thecasing at a point adjacent but below said pad, forming an opening in said casing at the inner end of thetun'nel formed, establishing a recycling line extending from the upper discharge end of said tubing above said pad to said opening and with the recycling line in sealed communication at its opposite ends with said tubing and the portions of said casing disposed about said opening, causing water to be pumped upwardly through said tubing from the lower end thereof, through said recycling line and to be freely discharged into said casing through said opening for free falling downwardly through said casing exteriorly of said tubing and impact with the water standing in said casing in said aquifer about said tubing and thereby generate energy waves in the water within the casing and aquifer to greatly enhance the cleaning action and selectively introducing cleaning chemicals into the recycling water.

2. The method of claim 1 including the step of selectively purging the mixed water and chemicals at the completion of a cleaning cycle.

3. The method of claim 2 including the step of introducing'an appropriate basic solution into the recycling water to produce an exothermic reaction and thereby elevate the temperature of the casing.

4. The method of claim 1 wherein said chemicals include concentrated potassium hypochlorite.

5. The method of claim 1 wherein said chemicals include a solution of sodium hexametaphosphate of between to 500 parts per million.

6. The method of claim 1 wherein said chemicals include hydrochloric acid inhibited at such a concentration as to protect all base metals.

I I t l l 

1. The method of cleaning and stimulating a water well of the type including an outer casing extending downwardly into an aquifer and perforated at the level of the aquifer and with the well casing being closed at its upper end by a support pad and having a central discharge tubing extending downwardly through the pad and the casing to at least the perforated area of the casing with the outer surface of the tubing spaced from the inner surfaces of the casing, said method including the steps of digging a pit downwardly alongside the pad to a level therebelow and tunneling inwardly to the casing at a point adjacent but below said pad, forming an opening in said casing at the inner end of the tunnel formed, establishing a recycling line extending from the upper discharge end of said tubing above said pad to said opening and with the recycling line in sealed communication at its opposite ends with said tubing and the portions of said casing disposed about said opening, causing water to be pumped upwardly through said tubing from the lower end thereof, through said recycling line and to be freely discharged into said casing through said opening for free falling downwardly through said casing exteriorly of said tubing and impact with the water standing in said casing in said aquifer about said tubing and thereby generate energy waves in the water within the casing and aquifer to greatly enhance the cleaning action and selectively introducing cleaning chemicals into the recycling water.
 2. The method of claim 1 including the step of selectively purging the mixed water and chemicals at the completion of a cleaning cycle.
 3. The method of claim 2 including the step of introducing an appropriate basic solution into the recycling water to produce an exothermic reaction and thereby elevate the temperature of the casing.
 4. The method of claim 1 wherein said chemicals include concentrated potassium hypochlorite.
 5. The method of claim 1 wherein said chemicals include a solution of sodium hexametaphosphate of between 100 to 500 parts per million.
 6. The method of claim 1 wherein said chemicals include hydrochloric acid inhibited at such a concentration as to protect all base metals. 